ALSA: ump: Fix evaluation of MIDI 1.0 FB info

commit 7be34f6feedd60e418de1c2c48e661d70416635f upstream.

The m1.0 field of UMP Function Block info specifies whether the given
FB is a MIDI 1.0 port or not.  When implementing the UMP support on
Linux, I somehow interpreted as if it were bit flags, but the field is
actually an enumeration from 0 to 2, where 2 means MIDI 1.0 *and* low
speed.

This patch corrects the interpretation and sets the right bit flags
depending on the m1.0 field of FB Info.  This effectively fixes the
missing detection of MIDI 1.0 FB when m1.0 is 2.

Fixes: 37e0e14128e0 ("ALSA: ump: Support UMP Endpoint and Function Block parsing")
Cc: <stable@vger.kernel.org>
Link: https://patch.msgid.link/20241127070059.8099-1-tiwai@suse.de
Signed-off-by: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

diff --git a/sound/core/ump.c b/sound/core/ump.c
index 0f0d7e895c5aa920f7533832de8440a6621a7a3a..e1cb96eeaf3111a3e600ad4f3dafc1d7b232e100 100644 (file)
--- a/sound/core/ump.c
+++ b/sound/core/ump.c
@@ -724,7 +724,10 @@ static void fill_fb_info(struct snd_ump_endpoint *ump,
        info->ui_hint = buf->fb_info.ui_hint;
        info->first_group = buf->fb_info.first_group;
        info->num_groups = buf->fb_info.num_groups;
-       info->flags = buf->fb_info.midi_10;
+       if (buf->fb_info.midi_10 < 2)
+               info->flags = buf->fb_info.midi_10;
+       else
+               info->flags = SNDRV_UMP_BLOCK_IS_MIDI1 | SNDRV_UMP_BLOCK_IS_LOWSPEED;
        info->active = buf->fb_info.active;
        info->midi_ci_version = buf->fb_info.midi_ci_version;
        info->sysex8_streams = buf->fb_info.sysex8_streams;